1. Field of the Invention
The present invention relates to image reproducing apparatus and method of selectively reproducing and outputting image data of an arbitrary angle from image data of a plurality of angles including a plurality of reproduction units.
2. Description of the Related Art
Conventionally, there has been commercially provided a multi-angle adaptive image reproducing apparatus of reproducing an optical disk on which images picked up at a plurality of camera angles are multiplexed and recorded as an angle block performed in the same time interval so that the image can be seen at a plurality of the angle. In a DVD-Video, one angle block can include a maximum of nine angle cells, and angle change is performed by shifting reproduced angle cells.
When the angle change is performed in a non-seamless manner, the angle cell is theoretically constructed with reproduction units VOBUs (Video OBject Units), and an address of the change destination VOBU of NSML_AGLI (non-seamless angle information) of an NV_PCK (Navigation Pack) recorded in the VOBU is acquired as angle change position information, thereby the angle change being performed. For example, in FIG. 15, when the angle change to an angle 1 is performed during reproduction of a VOBU 10 of an angle cell 2, an address of the change destination VOBU in the angle cell 1 of NSML_AGLI of an NV_PCK recorded in the VOBU 10 is acquired. If the address is a front end address of a VOBU 4, reproduction is performed from the VOBU 4. Similarly, when the angle change to an angle 3 is performed, an address of the change destination VOBU in the angle cell 3 of the NSML_AGLI of the NV_PCK recorded in the VOBU 10 is acquired, and the angle is changed to a front end of a VOBU 16.
When the angle change is performed in a seamless manner, the angle cell is constructed with ILVUs (InterLeaVed Units) including at least two VOBUs, and an address of the change destination ILVU of SML_AGLI (seamless angle information) of an NV_PCK (Navigation Pack) recorded in a VOBU of the ILVU is acquired as angle change position information, thereby the angle change being performed. For example, in FIG. 16, when the angle change to an angle 1 is performed during reproduction of an ILVU 10 of an angle cell 2, an address of the change destination ILVU in the angle cell 1 of SML_AGLI of an NV_PCK recorded in a VOBU of the ILVU 10 is acquired. If the address is a rear-end address of an ILVU 4, after the ILVU 10 is reproduced, the reproduction is performed from the ILVU 4. Similarly, when the angle change to an angle 3 is performed, an address of the change destination ILVU in the angle cell 3 of the SML_AGLI of the NV_PCK recorded in the ILVU 10 is acquired, and the angle is changed to a rear end of an ILVU 16.
In addition to the NSML_AGLI and the SML_AGLI, SML_PBI (seamless reproduction information) and VOBU_SRI (VOBU search information) are recorded in the NV_PCK. In the SML_PBI, ILVU_EA (rear-end address of an ILVU), NXT_ILVU_SA (start address of next ILVU), and NXT_ILVU_SZ (size of next ILVU) are recorded. In the VOBU_SRI, front end addresses of former and later VOBUs of the associated VOBU or front end addresses of VOBUs that are reproduced for 0.5xn seconds just-before and just-after the starting time point of the VOBU are recorded.
However, if the SML_AGLI recorded in the VOBU of the currently-reproduced ILVU at the time of angle change, the change destination address in the angle cell at the desired angle cannot be identified, so that the angle change cannot be performed. Therefore, there has been proposed an image reproducing apparatus for performing the angle change without delay by using the SML_AGLI recorded in the VOBU of the ILVU of another angle cell which is located in the same time interval as the currently-reproduced ILVU and multiplexed with the ILVU (for example, see Japanese Unexamined Patent Application Publication No. 2002-171472 (p3-p6, FIG. 1)).
However, in the aforementioned conventional image reproducing apparatus, if the SML_AGLI recorded in the VOBUs of the ILVU at all the angles cannot be acquired, the angle change may not be performed. In addition, in some cases, the change destination addresses of the angles at the ends of the angle cells are intentionally designated to 7FFFFFFFh. Like these cases, if the acquired change destination address is an unsuitable value, the angle change cannot be performed.